jvm参数调优-jvm.zip

# jvm 用于jvm参数调优学习 Test2 配置信息： /** * * -Xms20m -Xmx20m -Xmn1m -XX:SurvivorRatio=2 -XX:+PrintGCDetail -XX:+UseSerialGC * -Xms20m -Xmx20m -Xmn7m -XX:SurvivorRatio=2 -XX:+PrintGCDetail -XX:+UseSerialGC * -Xms20m -Xmx20m -Xmn7m -XX:NewRatio=2 -XX:+PrintGCDetail -XX:+UseSerialGC * * -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=d:/test2.dump * -Xss5m 栈内存 * -XX:PermSize=64M 方法区大小 * -XX:MaxPermSize=64M 方法区最大大小 * ************************************ * jdk1.8后，没有了方法区，改成了元数据区 Perm==> MateData * * -Xms20m:初始内存 * -Xmx20m:可扩展内存 * -Xmn7m:新生代内存 * -XX:SurvivorRatio=2 eden/from 或者 eden/to * -XX:NewRatio=2 老年代/新生代 */ Test1 配置信息：-Xmx20m -Xms5m -XX:+PrintCommandLineFlags -XX:+UseSerialGC -XX:+PrintGCDetails 日志信息： D:\java\jdk1.8.0_171\bin\java.exe -agentlib:jdwp=transport=dt_socket,address=127.0.0.1:50612,suspend=y,server=n -Xmx20m -Xms5m -XX:+PrintCommandLineFlags -XX:+UseSerialGC -XX:+PrintGCDetails -javaagent:D:\java\ideaIC-2018.2.1.win\lib\rt\debugger-agent.jar=file:/C:/Users/lhf/AppData/Local/Temp/capture.props -Dfile.encoding=UTF-8 -classpath D:\java\jdk1.8.0_171\jre\lib\charsets.jar;D:\java\jdk1.8.0_171\jre\lib\deploy.jar;D:\java\jdk1.8.0_171\jre\lib\ext\access-bridge-64.jar;D:\java\jdk1.8.0_171\jre\lib\ext\cldrdata.jar;D:\java\jdk1.8.0_171\jre\lib\ext\dnsns.jar;D:\java\jdk1.8.0_171\jre\lib\ext\jaccess.jar;D:\java\jdk1.8.0_171\jre\lib\ext\jfxrt.jar;D:\java\jdk1.8.0_171\jre\lib\ext\localedata.jar;D:\java\jdk1.8.0_171\jre\lib\ext\nashorn.jar;D:\java\jdk1.8.0_171\jre\lib\ext\sunec.jar;D:\java\jdk1.8.0_171\jre\lib\ext\sunjce_provider.jar;D:\java\jdk1.8.0_171\jre\lib\ext\sunmscapi.jar;D:\java\jdk1.8.0_171\jre\lib\ext\sunpkcs11.jar;D:\java\jdk1.8.0_171\jre\lib\ext\zipfs.jar;D:\java\jdk1.8.0_171\jre\lib\javaws.jar;D:\java\jdk1.8.0_171\jre\lib\jce.jar;D:\java\jdk1.8.0_171\jre\lib\jfr.jar;D:\java\jdk1.8.0_171\jre\lib\jfxswt.jar;D:\java\jdk1.8.0_171\jre\lib\jsse.jar;D:\java\jdk1.8.0_171\jre\lib\management-agent.jar;D:\java\jdk1.8.0_171\jre\lib\plugin.jar;D:\java\jdk1.8.0_171\jre\lib\resources.jar;D:\java\jdk1.8.0_171\jre\lib\rt.jar;D:\jvm\out\production\jvm_heap;D:\java\ideaIC-2018.2.1.win\lib\idea_rt.jar com.lhf.test.Test1 -XX:InitialHeapSize=5242880 -XX:MaxHeapSize=20971520 -XX:+PrintCommandLineFlags -XX:+PrintGCDetails -XX:+UseCompressedClassPointers -XX:+UseCompressedOops -XX:-UseLargePagesIndividualAllocation -XX:+UseSerialGC Connected to the target VM, address: '127.0.0.1:50612', transport: 'socket' [GC (Allocation Failure) [DefNew（新生代）: 1664K->192K(1856K), 0.0025363 secs] 1664K->616K(5952K), 0.0025815 secs] [Times: user=0.02 sys=0.00, real=0.00 secs] max memory:20316160 最大内存 free memory:5091096 空闲内存 total memory:6094848 使用内存 分配了1M内存 max memory:20316160 free memory:4042504 total memory:6094848 [GC (Allocation Failure) [DefNew: 1579K->61K(1856K), 0.0015465 secs][（老年代）Tenured: 1639K->1700K(4096K), 0.0111519 secs] 2004K->1700K(5952K), [Metaspace（元数据区，原来的perm）: 3251K->3251K(1056768K)], 0.0127612 secs] [Times: user=0.00 sys=0.00, real=0.01 secs] 分配了4M内存 max memory:20316160 free memory:4387968 total memory:10358784 结果为：391709 Disconnected from the target VM, address: '127.0.0.1:50612', transport: 'socket' Heap def new generation total 1920K, used 51K [0x00000000fec00000, 0x00000000fee10000, 0x00000000ff2a0000) eden space 1728K, 2% used [0x00000000fec00000, 0x00000000fec0ce18, 0x00000000fedb0000) from space 192K, 0% used [0x00000000fedb0000, 0x00000000fedb0000, 0x00000000fede0000) to space 192K, 0% used [0x00000000fede0000, 0x00000000fede0000, 0x00000000fee10000) tenured generation total 8196K, used 5796K [0x00000000ff2a0000, 0x00000000ffaa1000, 0x0000000100000000) the space 8196K, 70% used [0x00000000ff2a0000, 0x00000000ff8493f8, 0x00000000ff849400, 0x00000000ffaa1000) Metaspace used 3258K, capacity 4568K, committed 4864K, reserved 1056768K class space used 346K, capacity 392K, committed 512K, reserved 1048576K Process finished with exit code 0